1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Provides code common for host and device side USB. 4 * 5 * If either host side (ie. CONFIG_USB=y) or device side USB stack 6 * (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is 7 * compiled-in as well. Otherwise, if either of the two stacks is 8 * compiled as module, this file is compiled as module as well. 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/of.h> 14 #include <linux/platform_device.h> 15 #include <linux/usb/ch9.h> 16 #include <linux/usb/of.h> 17 #include <linux/usb/otg.h> 18 #include <linux/of_platform.h> 19 #include <linux/debugfs.h> 20 #include "common.h" 21 22 static const char *const ep_type_names[] = { 23 [USB_ENDPOINT_XFER_CONTROL] = "ctrl", 24 [USB_ENDPOINT_XFER_ISOC] = "isoc", 25 [USB_ENDPOINT_XFER_BULK] = "bulk", 26 [USB_ENDPOINT_XFER_INT] = "intr", 27 }; 28 29 /** 30 * usb_ep_type_string() - Returns human readable-name of the endpoint type. 31 * @ep_type: The endpoint type to return human-readable name for. If it's not 32 * any of the types: USB_ENDPOINT_XFER_{CONTROL, ISOC, BULK, INT}, 33 * usually got by usb_endpoint_type(), the string 'unknown' will be returned. 34 */ 35 const char *usb_ep_type_string(int ep_type) 36 { 37 if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names)) 38 return "unknown"; 39 40 return ep_type_names[ep_type]; 41 } 42 EXPORT_SYMBOL_GPL(usb_ep_type_string); 43 44 /** 45 * usb_otg_state_string() - returns human readable name of OTG state. 46 * @state: the OTG state to return the human readable name of. If it's not 47 * any of the states defined in usb_otg_state enum, 'UNDEFINED' will be 48 * returned. 49 */ 50 const char *usb_otg_state_string(enum usb_otg_state state) 51 { 52 static const char *const names[] = { 53 [OTG_STATE_A_IDLE] = "a_idle", 54 [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise", 55 [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon", 56 [OTG_STATE_A_HOST] = "a_host", 57 [OTG_STATE_A_SUSPEND] = "a_suspend", 58 [OTG_STATE_A_PERIPHERAL] = "a_peripheral", 59 [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall", 60 [OTG_STATE_A_VBUS_ERR] = "a_vbus_err", 61 [OTG_STATE_B_IDLE] = "b_idle", 62 [OTG_STATE_B_SRP_INIT] = "b_srp_init", 63 [OTG_STATE_B_PERIPHERAL] = "b_peripheral", 64 [OTG_STATE_B_WAIT_ACON] = "b_wait_acon", 65 [OTG_STATE_B_HOST] = "b_host", 66 }; 67 68 if (state < 0 || state >= ARRAY_SIZE(names)) 69 return "UNDEFINED"; 70 71 return names[state]; 72 } 73 EXPORT_SYMBOL_GPL(usb_otg_state_string); 74 75 static const char *const speed_names[] = { 76 [USB_SPEED_UNKNOWN] = "UNKNOWN", 77 [USB_SPEED_LOW] = "low-speed", 78 [USB_SPEED_FULL] = "full-speed", 79 [USB_SPEED_HIGH] = "high-speed", 80 [USB_SPEED_WIRELESS] = "wireless", 81 [USB_SPEED_SUPER] = "super-speed", 82 [USB_SPEED_SUPER_PLUS] = "super-speed-plus", 83 }; 84 85 static const char *const ssp_rate[] = { 86 [USB_SSP_GEN_UNKNOWN] = "UNKNOWN", 87 [USB_SSP_GEN_2x1] = "super-speed-plus-gen2x1", 88 [USB_SSP_GEN_1x2] = "super-speed-plus-gen1x2", 89 [USB_SSP_GEN_2x2] = "super-speed-plus-gen2x2", 90 }; 91 92 /** 93 * usb_speed_string() - Returns human readable-name of the speed. 94 * @speed: The speed to return human-readable name for. If it's not 95 * any of the speeds defined in usb_device_speed enum, string for 96 * USB_SPEED_UNKNOWN will be returned. 97 */ 98 const char *usb_speed_string(enum usb_device_speed speed) 99 { 100 if (speed < 0 || speed >= ARRAY_SIZE(speed_names)) 101 speed = USB_SPEED_UNKNOWN; 102 return speed_names[speed]; 103 } 104 EXPORT_SYMBOL_GPL(usb_speed_string); 105 106 /** 107 * usb_get_maximum_speed - Get maximum requested speed for a given USB 108 * controller. 109 * @dev: Pointer to the given USB controller device 110 * 111 * The function gets the maximum speed string from property "maximum-speed", 112 * and returns the corresponding enum usb_device_speed. 113 */ 114 enum usb_device_speed usb_get_maximum_speed(struct device *dev) 115 { 116 const char *p = "maximum-speed"; 117 int ret; 118 119 ret = device_property_match_property_string(dev, p, ssp_rate, ARRAY_SIZE(ssp_rate)); 120 if (ret > 0) 121 return USB_SPEED_SUPER_PLUS; 122 123 ret = device_property_match_property_string(dev, p, speed_names, ARRAY_SIZE(speed_names)); 124 if (ret > 0) 125 return ret; 126 127 return USB_SPEED_UNKNOWN; 128 } 129 EXPORT_SYMBOL_GPL(usb_get_maximum_speed); 130 131 /** 132 * usb_get_maximum_ssp_rate - Get the signaling rate generation and lane count 133 * of a SuperSpeed Plus capable device. 134 * @dev: Pointer to the given USB controller device 135 * 136 * If the string from "maximum-speed" property is super-speed-plus-genXxY where 137 * 'X' is the generation number and 'Y' is the number of lanes, then this 138 * function returns the corresponding enum usb_ssp_rate. 139 */ 140 enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev) 141 { 142 const char *maximum_speed; 143 int ret; 144 145 ret = device_property_read_string(dev, "maximum-speed", &maximum_speed); 146 if (ret < 0) 147 return USB_SSP_GEN_UNKNOWN; 148 149 ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed); 150 return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret; 151 } 152 EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate); 153 154 /** 155 * usb_state_string - Returns human readable name for the state. 156 * @state: The state to return a human-readable name for. If it's not 157 * any of the states devices in usb_device_state_string enum, 158 * the string UNKNOWN will be returned. 159 */ 160 const char *usb_state_string(enum usb_device_state state) 161 { 162 static const char *const names[] = { 163 [USB_STATE_NOTATTACHED] = "not attached", 164 [USB_STATE_ATTACHED] = "attached", 165 [USB_STATE_POWERED] = "powered", 166 [USB_STATE_RECONNECTING] = "reconnecting", 167 [USB_STATE_UNAUTHENTICATED] = "unauthenticated", 168 [USB_STATE_DEFAULT] = "default", 169 [USB_STATE_ADDRESS] = "addressed", 170 [USB_STATE_CONFIGURED] = "configured", 171 [USB_STATE_SUSPENDED] = "suspended", 172 }; 173 174 if (state < 0 || state >= ARRAY_SIZE(names)) 175 return "UNKNOWN"; 176 177 return names[state]; 178 } 179 EXPORT_SYMBOL_GPL(usb_state_string); 180 181 static const char *const usb_dr_modes[] = { 182 [USB_DR_MODE_UNKNOWN] = "", 183 [USB_DR_MODE_HOST] = "host", 184 [USB_DR_MODE_PERIPHERAL] = "peripheral", 185 [USB_DR_MODE_OTG] = "otg", 186 }; 187 188 /** 189 * usb_get_dr_mode_from_string() - Get dual role mode for given string 190 * @str: String to find the corresponding dual role mode for 191 * 192 * This function performs a lookup for the given string and returns the 193 * corresponding enum usb_dr_mode. If no match for the string could be found, 194 * 'USB_DR_MODE_UNKNOWN' is returned. 195 */ 196 static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str) 197 { 198 int ret; 199 200 ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str); 201 return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret; 202 } 203 204 enum usb_dr_mode usb_get_dr_mode(struct device *dev) 205 { 206 const char *dr_mode; 207 int err; 208 209 err = device_property_read_string(dev, "dr_mode", &dr_mode); 210 if (err < 0) 211 return USB_DR_MODE_UNKNOWN; 212 213 return usb_get_dr_mode_from_string(dr_mode); 214 } 215 EXPORT_SYMBOL_GPL(usb_get_dr_mode); 216 217 /** 218 * usb_get_role_switch_default_mode - Get default mode for given device 219 * @dev: Pointer to the given device 220 * 221 * The function gets string from property 'role-switch-default-mode', 222 * and returns the corresponding enum usb_dr_mode. 223 */ 224 enum usb_dr_mode usb_get_role_switch_default_mode(struct device *dev) 225 { 226 const char *str; 227 int ret; 228 229 ret = device_property_read_string(dev, "role-switch-default-mode", &str); 230 if (ret < 0) 231 return USB_DR_MODE_UNKNOWN; 232 233 return usb_get_dr_mode_from_string(str); 234 } 235 EXPORT_SYMBOL_GPL(usb_get_role_switch_default_mode); 236 237 /** 238 * usb_decode_interval - Decode bInterval into the time expressed in 1us unit 239 * @epd: The descriptor of the endpoint 240 * @speed: The speed that the endpoint works as 241 * 242 * Function returns the interval expressed in 1us unit for servicing 243 * endpoint for data transfers. 244 */ 245 unsigned int usb_decode_interval(const struct usb_endpoint_descriptor *epd, 246 enum usb_device_speed speed) 247 { 248 unsigned int interval = 0; 249 250 switch (usb_endpoint_type(epd)) { 251 case USB_ENDPOINT_XFER_CONTROL: 252 /* uframes per NAK */ 253 if (speed == USB_SPEED_HIGH) 254 interval = epd->bInterval; 255 break; 256 case USB_ENDPOINT_XFER_ISOC: 257 interval = 1 << (epd->bInterval - 1); 258 break; 259 case USB_ENDPOINT_XFER_BULK: 260 /* uframes per NAK */ 261 if (speed == USB_SPEED_HIGH && usb_endpoint_dir_out(epd)) 262 interval = epd->bInterval; 263 break; 264 case USB_ENDPOINT_XFER_INT: 265 if (speed >= USB_SPEED_HIGH) 266 interval = 1 << (epd->bInterval - 1); 267 else 268 interval = epd->bInterval; 269 break; 270 } 271 272 interval *= (speed >= USB_SPEED_HIGH) ? 125 : 1000; 273 274 return interval; 275 } 276 EXPORT_SYMBOL_GPL(usb_decode_interval); 277 278 #ifdef CONFIG_OF 279 /** 280 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device 281 * which is associated with the given phy device_node 282 * @np: Pointer to the given phy device_node 283 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for 284 * phys which do not have phy-cells 285 * 286 * In dts a usb controller associates with phy devices. The function gets 287 * the string from property 'dr_mode' of the controller associated with the 288 * given phy device node, and returns the correspondig enum usb_dr_mode. 289 */ 290 enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0) 291 { 292 struct device_node *controller; 293 struct of_phandle_args args; 294 const char *dr_mode; 295 int index; 296 int err; 297 298 for_each_node_with_property(controller, "phys") { 299 if (!of_device_is_available(controller)) 300 continue; 301 index = 0; 302 do { 303 if (arg0 == -1) { 304 args.np = of_parse_phandle(controller, "phys", 305 index); 306 args.args_count = 0; 307 } else { 308 err = of_parse_phandle_with_args(controller, 309 "phys", "#phy-cells", 310 index, &args); 311 if (err) 312 break; 313 } 314 315 of_node_put(args.np); 316 if (args.np == np && (args.args_count == 0 || 317 args.args[0] == arg0)) 318 goto finish; 319 index++; 320 } while (args.np); 321 } 322 323 finish: 324 err = of_property_read_string(controller, "dr_mode", &dr_mode); 325 of_node_put(controller); 326 327 if (err < 0) 328 return USB_DR_MODE_UNKNOWN; 329 330 return usb_get_dr_mode_from_string(dr_mode); 331 } 332 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy); 333 334 /** 335 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported 336 * for given targeted hosts (non-PC hosts) 337 * @np: Pointer to the given device_node 338 * 339 * The function gets if the targeted hosts support TPL or not 340 */ 341 bool of_usb_host_tpl_support(struct device_node *np) 342 { 343 return of_property_read_bool(np, "tpl-support"); 344 } 345 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support); 346 347 /** 348 * of_usb_update_otg_caps - to update usb otg capabilities according to 349 * the passed properties in DT. 350 * @np: Pointer to the given device_node 351 * @otg_caps: Pointer to the target usb_otg_caps to be set 352 * 353 * The function updates the otg capabilities 354 */ 355 int of_usb_update_otg_caps(struct device_node *np, 356 struct usb_otg_caps *otg_caps) 357 { 358 u32 otg_rev; 359 360 if (!otg_caps) 361 return -EINVAL; 362 363 if (!of_property_read_u32(np, "otg-rev", &otg_rev)) { 364 switch (otg_rev) { 365 case 0x0100: 366 case 0x0120: 367 case 0x0130: 368 case 0x0200: 369 /* Choose the lesser one if it's already been set */ 370 if (otg_caps->otg_rev) 371 otg_caps->otg_rev = min_t(u16, otg_rev, 372 otg_caps->otg_rev); 373 else 374 otg_caps->otg_rev = otg_rev; 375 break; 376 default: 377 pr_err("%pOF: unsupported otg-rev: 0x%x\n", 378 np, otg_rev); 379 return -EINVAL; 380 } 381 } else { 382 /* 383 * otg-rev is mandatory for otg properties, if not passed 384 * we set it to be 0 and assume it's a legacy otg device. 385 * Non-dt platform can set it afterwards. 386 */ 387 otg_caps->otg_rev = 0; 388 } 389 390 if (of_property_read_bool(np, "hnp-disable")) 391 otg_caps->hnp_support = false; 392 if (of_property_read_bool(np, "srp-disable")) 393 otg_caps->srp_support = false; 394 if (of_property_read_bool(np, "adp-disable") || 395 (otg_caps->otg_rev < 0x0200)) 396 otg_caps->adp_support = false; 397 398 return 0; 399 } 400 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps); 401 402 /** 403 * usb_of_get_companion_dev - Find the companion device 404 * @dev: the device pointer to find a companion 405 * 406 * Find the companion device from platform bus. 407 * 408 * Takes a reference to the returned struct device which needs to be dropped 409 * after use. 410 * 411 * Return: On success, a pointer to the companion device, %NULL on failure. 412 */ 413 struct device *usb_of_get_companion_dev(struct device *dev) 414 { 415 struct device_node *node; 416 struct platform_device *pdev = NULL; 417 418 node = of_parse_phandle(dev->of_node, "companion", 0); 419 if (node) 420 pdev = of_find_device_by_node(node); 421 422 of_node_put(node); 423 424 return pdev ? &pdev->dev : NULL; 425 } 426 EXPORT_SYMBOL_GPL(usb_of_get_companion_dev); 427 #endif 428 429 struct dentry *usb_debug_root; 430 EXPORT_SYMBOL_GPL(usb_debug_root); 431 432 DEFINE_MUTEX(usb_dynids_lock); 433 EXPORT_SYMBOL_GPL(usb_dynids_lock); 434 435 static int __init usb_common_init(void) 436 { 437 usb_debug_root = debugfs_create_dir("usb", NULL); 438 ledtrig_usb_init(); 439 return 0; 440 } 441 442 static void __exit usb_common_exit(void) 443 { 444 ledtrig_usb_exit(); 445 debugfs_remove_recursive(usb_debug_root); 446 } 447 448 subsys_initcall(usb_common_init); 449 module_exit(usb_common_exit); 450 451 MODULE_DESCRIPTION("Common code for host and device side USB"); 452 MODULE_LICENSE("GPL"); 453